Seat belts as passenger-restraining devices have come to be used universally to improve the safety of the occupants of vehicles. Although passenger restraint belt systems are arranged in various ways, nearly all systems have at least one belt which winds onto and unwinds from a belt retractor. For example, the belt retractor may be employed in a two-point type belt system in which a fixed end of the belt is secured to either the lower portion of the vehicle on the inboard side of the seat of the upper portion of the vehicle on the outboard side. In the first instance the retractor is secured to the vehicle adjacent to the seat on the outboard side, while in the latter case the retractor is disposed next to the seat on the inboard side. In a three-point type belt system the respective ends of a single continuous lap and shoulder belt are anchored to upper and lower portions of the vehicle on the outboard side of the seat. A control belt is attached at one end to guide a ring which receives the intermediate portion of the continous belt and winds onto and unwinds from a retractor located adjacent to the seat on the inboard side.
In most restraint belt systems the retractor exerts a constant belt-winding force on the belt, thereby automatically and continuously adjusting the belt system to fit the individual passenger. An undesirable aspect of the adjusting feature provided by a continuously working retractor, however, is the constant pressure of the tensioned restraint belt (or belts) exerted on the passenger.
In the case of a waist or lap restraint belt (which extends from side to side over the lower part of the vehicle seat) the passenger becomes locally uncomfortable over the length of the retractor belt which is constantly pressed against the mid-section of his or her body. Similarly, the passenger subjected to a shoulder belt extending diagonally across his or her upper body experiences the uncomfortable feeling of being continually pulled toward the seat back. In order to increase the use of seat belt restraint systems, it is desirable to make them as comfortable as possible and eliminate all undesirable characteristics such as the uncomfortable retracting force described above.
It is, therefore, an object of the present invention to provide a seat belt guide for use in vehicle seat belt restraint systems which is capable of clamping a restraint belt and locking it against retraction while in use, thereby eliminating the discomfort normally associated with wearing a constantly tensioned restraint belt.
It is a further object of the present invention to provide a seat belt guide as described above on a pivotable support arm which is pivotably connected to the side of a seat and is linked to a mounting bracket for a pivotable seat back so that when the seat back is pivoted forward, the seat belt is prevented from being clamped between the seat and the seat back.